Low-cost antenna/detector modules are a key component in passive microwave links, low-data-rate local area networks (LANs), and wireless electronic shelf labels used in the wireless supermarket. The architecture of these systems is typically based on modulated backscattering, which is simply a short-range digital radio link transmitting data by means of a modulated scatterer. One type of antenna used in such systems is the L-shaped inverted-F radiator (LIFA antenna) designed for use in a wireless LAN modem, as described in the article written by N. Erkocevic in the publication entitled "Antenna For Wireless LAN Modem," IEEE First Symposium on Communications and Vehicular Technology in the Benelux, Oct. 27-28, 1991, Delft, The Netherlands. There is a continuing need to improve the design of the antenna and associated circuit to further enhance the sensitivity and bandwidth of such systems.